Elm327 or similar device

[Weatheralls Auto]

http://60degreev6.com/forum/local_links.php?catid=9&page=1#linkid142

Another Update while I test more Pcms and wait for the Hardware to be ready.

Not all Pcms have Mode 09 Pid 02 to report Vin# (1999 Venture for example)
So it took me a bit but have now change to 3c 01,02,03

Cleaned up some code for error traps and added Voltage report and some other details.

Zip now contains all Text files so more Vista friendly.

Next is Minimize to SysTray and Title is TaskBar

Please Send me any Unsupported Osids you come across with the Number and Veh info so it can be added.

Located here -> http://60degreev6.com/forum/local_li...ge=1#linkid142

[robertisaar]

What are you using to connect to the PCM?

hardware or software wise?

[Weatheralls Auto]

Hardware, need something J1850 VPW compliant.

[robertisaar]

odd... if i have the program open and the correct port selected, when i key-on, the display shows a little bit of something, but i have no idea what it is...

[Weatheralls Auto]

If your hardware doesnt interpret the J1850 vpw protocol you will see wierd characters.

Type AT Z or AT I and see what returns

[robertisaar]

i do remember hitting those buttons, but no results.

[3400-95-Modified]

If your still wanting to use a tool to make your own write utility then a good hardware to start with would be the AVT devices. Its the same stuff that Tuner Cat, and DHP used to use. IIRC he still sells them.

https://www.AVT-HQ.com

[Weatheralls Auto]

Yes, I have looked at them.

I am researching another right now as it is way cheaper, wanting to keep the cost down so the DIYers will be more interested.

I think more would get into tuning themselves if cost was around $100

[Weatheralls Auto]

Well my mind is mush, soooo much reading!!

Uploading another Update, probably the last for a while till I get either or both PCM read/write implemented.

http://60degreev6.com/forum/local_links.php?catid=9&page=1#linkid142

[dimented24x7]

Without HighSpeed I know I can not flash, but hoping to be able to dump the bin from PCM with the Elm327

Maybe dimented24x7 can chime in here

I dont think the high speed is required for downloads. I couldnt find a reference to it. I recall it being required somewhere, probably for a reflash.

The only potential issue with the downloads is teh size of the data being sent.

In addition to the header, you need to send the 24 bit address of what you want to download, followed by a 16-bit value defining the size of the download, followed by a 16-bit checksum. So, just getting a download in motion requires a pretty large frame. When you do an actual download, the PCM will rapidly transmit the requested data, which could potentially overwhelm the elm, if it allows you to transmit large frames to begin with.

Check this out. I forgot I had this. This is an excel sheet that I made that has a basic listing of the commands related to uploads/downloads/reflashing. You could try some of these and see what you get. For a download, you may find that some areas are protected. If you know what flash chip your PCM uses, you can get an idea of what the accessable addresses are. The PCM will not allow you to access certain things, such as hardware or RAM as it may cause the PCM to become unstable.

[dimented24x7]

That app looks pretty cool, BTW. I want to try it out on mine. Just out of curiosity, how long did it take you to brute force the key?

[Weatheralls Auto]

8 hours to 24 hours so far on the 4 I have done.

Though, I have run into an issue, all this has been done on a bench setup.
I have since tried a few in the shop with no success. There is too much chatter on the DataLine and have to either silence it and or filter it.

[dimented24x7]

Thats one thing Ive heard is that some of the devices on the bus may still transmit even when a command to silence all nodes has been issued. I can imagine this being especially true for later model cars. I have a later model 3.5L malibu maxx and it seems like just about everything is on the OBD bus transmitting data, the DIC, radio, BCM, dash, etc.

[robertisaar]

so... OBD2 has silence commands, but they don't do what they're supposed to?

i'm so happy with my outdated OBD1 stuff...

[dimented24x7]

Thats what Ive heard, anyway.

Planet,

What problems where you having? Is it an issue of sorting out the data, or the elm giving errors and dumping the frames? In the datasheet, it says that the elm has no buffer, so if the IC is busy, it will potentially miss data.